188 Annals of the Carnegie Museum. 



Dimensions in millimeters : Abdomen cJ* 26.5-28 (Chapada), 26.5- 

 29.5 (Sapucay) ; $ 27 (Chapada), 26-27 (Sapucay). Hind wing 

 c? 17-19 (Chapada), 18-19. 5 (Sapucay) ; 9 18-19. 5 (Chapada), 

 19 (Sapucay). Width of tip of bifid dorsal process of abdominal 

 segment 10 of cT, rear view, .66 ; maximum width of segment 10 of 

 d\ rear view, .84. 



Habitat: — Brazil, Sete Lagoas, Minas Geraes, May 3 and 4, 

 1908, by J. D. Haseman, 2 d\ Carnegie Museum, Pittsburgh. 



Chapada, by H. H. Smith, 8 $ and parts of 20 others, 1 $ and 

 parts of 4 others; collector's numbers 11, 16, 115, 189, 197. Car- 

 negie Museum, Pittsburgh. 



Paraguay, Sapucay, by W. T. Foster, November, 1899, to 

 February, 1900, 6 (?, 2 $, January 17, 1903, 1 cT numbered 59 

 (other males numbered 59 are Oxyagrion impunctatum n. sp.). U. 

 S. National Museum. 



94. Oxyagrion impunctatum, sp. nov. 

 (Plate III, figs. 56, 57.) 



d\ Vertex obscure, brownish, with traces of a pale spot on each side 

 somewhat anterior to the area occupied by the postocular spot in allied 

 genera ; face carmine red ; labium and rear of head yellow. 



Prothorax brownish-yellow, its grooves and sutures occupied by 

 black lines, its hind margin low, convex. Dorsum of meso-metathorax 

 reddish brown or olive ; sides and pectus paler, greenish-yellow ; a 

 short black mark at the upper ends of the humeral and lateral sutures. 



Abdominal segments 1 and 2 yellowish, brown or red above ; a pair 

 of small mid- dorsal blackish spots on 1, a transverse dorsal blackish 

 mark at three-fourths' length of 2 ; 3-10 red, more obscure on 7-10 ; 

 a transverse black line on the intersegmental articulations of 3-6 in 

 some. 



Segment 10 and the appendages very similar to those of O. basale, 

 i. e., hind dorsal margin of 10 broadly excised in a concave curve, 

 margins of the excision elevated and produced at the hind end on each 

 side into an acute process, which is directed more nearly upward 

 (dorsad) and not so much caudad and dorsad as is the case in O. basale; 

 in rear view also this dorsal process is very similar to that of O. basale, 

 but its lateral margins are nearly parallel, instead of diverging as in 

 O. basale. 



Superior appendages directed downward (ventrad) as well as caudad, 



